Genetic Considerations

Mutations in the SERPINA1 gene cause alpha-1 antitrypsin (AAT) deficiency. The gene (AT1) causes the hereditary form of emphysema. AT1 protects the body from being damaged by the protinase trypsin. AT1 is inherited in an autosomal co-dominant pattern, meaning that two different gene alleles are expressed and both contribute to the development of the trait. The M allele is most common and results in production of normal levels of AT1. People who are homozygous normal have copies of the M allele from both parents. The two variants (S and Z) cause production of low or moderately low amounts of AT1. Persons with the ZZ or SZ genotype will probably develop AT1 deficiency. Persons with an MS or SS genotype usually produce enough alpha-1 antitrypsin to protect the lungs. There is an increased risk of AT1 for those who carry the MZ alleles, particularly if they are smokers. Familial factors predisposing to emphysema in the absence of alpha-1 antitrypsin deficiency are also likely.

Among the evils which a vitiated appetite has fastened upon mankind, those that arise from the use of Tobacco hold a prominent place, and call loudly for reform. We pity the poor Chinese, who stupifies body and mind with opium, and the wretched Hindoo, who is under a similar slavery to his favorite plant, the Betel but we present the humiliating spectacle of an enlightened and christian nation, wasting annually more than twenty-five millions of dollars, and destroying the health and the lives of thousands, by a practice not at all less degrading than that of the Chinese or Hindoo.